JPH0778393B2 - Vane compressor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vane compressor in which a space between a cylinder and a rotor is divided into a plurality of vanes to form a compression chamber.

[Prior Art] In this type of compressor, a cylindrical rotor peripheral surface housed in a substantially elliptical cylinder composed of a sine cam curve or an upwardly convex curve that approximates this curve and a cylinder in the region of the cylinder on the minor axis side The rotor is fitted and accommodated in the cylinder so that the inner peripheral surface has a minute clearance, and the region of the minute clearance provides a sealing property between the cylinder inner peripheral surface and the rotor peripheral surface. A discharge port is provided in front of the seal region in the rotation direction of the rotor, and a suction port is provided on the passage side of the seal region, so that the compression chamber communicating with the discharge port communicates with the suction port. The seal area prevents leakage of high pressure refrigerant gas into the chamber.

In such a configuration, the positional relationship between the seal area and the discharge port affects the compression efficiency of the refrigerant gas, but if overcompression avoidance is taken into consideration, part of the discharge port must be on the boundary of the seal region. Is ideal. That is, in a state where the discharge port is away from the seal region, the refrigerant gas remains between the vane and the seal region even after the vane passes through the discharge port, and overcompression of the residual refrigerant gas leading to a drive loss of the compressor. The inconvenience that this occurs is caused. This inconvenience can be avoided by hanging a part of the discharge port on the boundary of the seal area. Moreover, when the fulcrum of the discharge valve that opens and closes the discharge port on the discharge chamber side is on the opposite side of the suction port adjacent to the discharge port, bending fatigue of the discharge valve itself caused by the opening / closing operation of the discharge valve may occur. The discharge valve can be lengthened so that it can be suppressed. If the discharge port is separated from the seal area, the length of the discharge valve becomes short, and bending fatigue becomes severe.

[Problems to be Solved by the Invention] While the above-described advantages are obtained by bringing the discharge port closer to the seal region, the gap between the inner circumferential surface of the cylinder and the rotor in front of the discharge port becomes small, and The cross-sectional area before passing is very small. Such a reduction in the passage cross-sectional area makes the passage resistance of the refrigerant gas to the discharge port extremely high especially at the time of high speed rotation, and the large passage resistance hinders the smooth discharge of the refrigerant gas. Therefore, for example, as disclosed in Japanese Patent Publication No. 39-4787, there is a means for extending and forming the introduction groove before and after the discharge port in the rotation direction of the rotor and appropriately separating the discharge port from the seal area. However, if the extension length of the introduction groove is made too large, the communication time between the adjacent compression chambers via the vanes will be shortened and the compression efficiency will be reduced. Suppression cannot be achieved.

Also, at the connection between the arc curve of the cylinder inner peripheral surface in the seal area and the curve protruding upward, there is a large angle, and the acceleration of the vane in the direction of immersion is large, so that the vane moves from the cylinder inner peripheral surface of the arc curve. Easy to separate. Such discontinuous sliding of the vanes causes a collision between the inner peripheral surface of the cylinder and the vane, and damage to the inner peripheral surface of the cylinder at the collision site is unavoidable.

An object of the present invention is to provide a vane compressor capable of achieving a smooth discharge action while preventing discontinuous sliding contact of vanes.

[Means for Solving the Problem] Therefore, in the present invention, the cylinder inner peripheral surface between the discharge port arranged at the end of the upward convex curved region such as the sine cam curve and the suction port adjacent to the discharge port. Is provided with a circular arc-shaped seal area having a radius substantially matching the radius of the rotor, and the cylinder inner peripheral surface between the seal area and the discharge port is smoothly connected to the circular arc curve and convex curve of the seal area. A buffer region formed of a curve is provided, an introduction groove extending forward and backward in the rotation direction of the rotor is connected to the discharge port, and an extension boundary on the rear side of the introduction groove is set near the boundary of the seal region. However, the passage cross-section area between the boundary of the introduction groove and the rotor is equal to or larger than the passage cross-section area between the rotor and the inner peripheral surface portion of the cylinder corresponding to the extension boundary on the front side of the introduction groove. The boundary position was set.

[Operation] An arc curve and a convex curve such as a sine cam curve are connected by, for example, a cubic curve. As a result, the vane makes a smooth sliding transition from the convex curved region to the cushioning region, and a smooth sliding transition from the cushioning region to the sealing region. Therefore, the discontinuous sliding contact of the vane with the inner peripheral surface of the cylinder is eliminated, and damage to the inner peripheral surface of the cylinder due to the discontinuous sliding contact is avoided.

Further, between the inner peripheral surface portion and the rotor of the cylinder area sum sigma ₁ pass section Cs ₁ corresponds to the extended boundary of the front guide grooves between the boundary and the rotor of the guide grooves of the passage cross section Cs ₂ Area Σ ₂
By setting the boundary position of the introduction groove as described above, the ejection resistance in the passage cross section Cs ₁ between the boundary of the introduction groove and the rotor can be made equal to or less than the ejection resistance in the passage cross section Cs ₂ . Therefore, it is possible to achieve an appropriate balance between the ejection resistance at the ejection port and the ejection resistance at the passage cross section Cs ₂ , and based on this balance achievement, the passage cross section Cs ₂
A smooth discharge action can be achieved by setting the extension boundary on the front side of the introduction groove so that the discharge resistance in the above is suppressed and the communication between the adjacent compression chambers via the vane is performed at an appropriate time. .

[Embodiment] An embodiment in which the present invention is embodied in a variable capacity vane compressor will be described below with reference to the drawings.

As shown in FIG. 3, a cylinder 3 is housed and fixed in a pair of front and rear housings 1 and 2 which are joined and fixed, and side plates 4 and 5 are closely joined to both front and rear ends of the cylinder 3. The inside of the cylinder 3 is formed into a substantially elliptic cylindrical chamber, and a cylindrical rotor 6 is fitted and housed in the cylinder chamber so as to be rotatable in the direction of arrow P in FIG. The rotor 6 is fitted with a minute clearance in a region on the minor axis side of the inner peripheral surface of the substantially elliptical cylinder, and the regions of this minute clearance are the seal regions S ₁ and S ₂ .

Support shafts 6a and 6b are integrally formed on the front and rear of the rotor 6,
The front side plate 4 and the rear side plate 5 are rotatably supported. A plurality of grooves 7 (four in this embodiment) are formed in the circumferential surface of the rotor 6 in the radial direction, and vanes 8 are formed in each groove 7 in the front and rear side plates.
It is slidably fitted and supported in close contact with 4,5. The bottom of the groove 7 communicates with the oil separation chamber 2a at the rear of the rear housing 2 so that the lubricating oil stored in the oil separation chamber 2a can be supplied to the bottom of the groove 7. Each vane 8 is a rotor 6
The can contact in the cylinder peripheral surface by the pressure of the groove 7 bottom communicating with the centrifugal force and the oil separation chamber 2a with the rotation, the cylinder chamber is a plurality of the plurality of vanes 8 and the sealing area S _1, S ₂ It is divided into compression chambers R ₁ , R ₂ and R ₃ .

The cylinder 3 has a pair of intake passages 9A, 9B that penetrate axially therethrough.
Is provided and the intake ports 10A, 10 that open to the cylinder chamber
B is connected to the suction passages 9A and 9B with an angle difference of 180 °. Both suction ports 10A, 10B are arranged and set on the passage sides of the seal regions S ₁ , S ₂ in the rotation direction P of the rotor 6.

A pair of discharge chambers 3a and 3b are provided in the vicinity of the suction passages 9A and 9B in the circumferential direction of the cylinder 3, and the discharge ports 11A and 11B opening to the cylinder chamber have an angle difference of 180 °.
It is connected to a and 3b. In this embodiment, one discharge chamber 3a
Three discharge ports 11A (or 11B) are formed correspondingly (or 3b). Both the discharge ports 11A, 11B are arranged set in front of the seal region S _1, S ₂ in the rotational direction of the rotor 6, the discharge chamber 3a, the discharge valve 12A at the 3b, it is opened and closed by 12B.

Introducing grooves 11a and 11b are connected to the discharge ports 11A and 11B in the rotational direction of the rotor 6. As shown in FIG. 2 (b), the width W of the introduction grooves 11a, 11b is set to be equal to or larger than the diameter of the discharge ports 11A, 11B, and the extension of the introduction grooves 11a, 11b in the rotation direction of the rotor 6 on the rear side. The boundary d ₁ is set on the boundary between the seal areas S ₁ and S ₂ . Then, the introduction groove 11 in the rotation direction of the rotor 6
The extended boundary d ₂ on the front side of a, the lateral boundaries d ₃ and d ₄ and the extended boundary d ₁
The area (= Σ ₁ ) obtained by multiplying the area σ of the cross section Cs ₁ (the area indicated by the diagonal lines in FIG. 2B) between the rotor 6 and the rotor 6 by the number of the discharge ports 11A (3) (= Σ ₁ ) is the front extension boundary. Area Σ of passage cross section Cs ₂ between the cylinder peripheral surface portion corresponding to d ₂ and the rotor 6
₂ (regional area sandwiched between the cylinder 3 and the rotor 6 in FIG. 3) or more. Position of the extending boundary d ₂ such that the area sigma ₁ pass section Cs ₁ is passed sectional Cs ₂ area sigma ₂ or in other words are set. A passing cross section between the extending boundary d ₂ and the rotor 6 is shown by a chain line K in FIGS. 2A and 2B, and a passing cross-sectional area σ is a chain line K and a boundary d in FIG. 2B. ₃ is twice the area of the substantially triangular region formed by the circular curve C ′ ₀ of the rotor 6 and (the length of the chain line K) × (the width W of the introduction groove 11a).

The refrigerant gas introduced into the suction chamber 1a between the front housing 1 and the front side plate 4 is introduced into the cylinder chamber through the suction passage 4a of the front side plate 4 and the suction passages 9A, 9B, and then the discharge port 11A, 11B to discharge valve 1
2A and 12B are pushed away and discharged into the discharge chambers 3a and 3b. An annular capacity control plate 13 is interposed between the rotor 6 and the front side plate 4 so as to be rotatable around a support shaft 6a.
The capacity control plate 13 is provided with auxiliary passages 13a and 13b that connect the suction passage 4a and the cylinder chamber. Therefore, by rotating the capacity control plate 13, the compression chambers R ₁ , R ₂ and R ₃ are moved by the vane 8.
The period of communication between the cylinder chamber and the auxiliary passages 13a, 13b is changed, and thereby the suction capacity into the cylinder chamber,
That is, the volume discharged to the discharge chambers 3a and 3b can be controlled. This control is performed by the pressure resistance between the discharge pressure and the suction pressure via the spool 14 in the front side plate 4, and the sliding displacement of the spool 14 due to this pressure resistance causes the pin 15 to move.
Is converted into rotation of the capacity control plate 13 via.

As shown in FIG. 1, when the radius vector from the rotation axis l of the rotor 6 to the inner peripheral surface of the cylinder 3 is r and the rotation angle from the starting end line L of the radius vector r to the radius vector r is θ, the seal area is angular range S ₁ in the angle range _{-θ 1/2 ≦ θ ≦ θ} 1/2 and the seal region S ₂ [pi
Curve of the inner peripheral surface of _{-θ 1/2 ≦ θ ≦ π} + θ 1/2 In the cylinder 3 is a circular arc curve of slightly larger radius R than the radius of the rotor 6. In FIG. 4, C ₀ is shown on the horizontal axis representing r = R.

theta _1/2 + In the angular range of _{θ 6 ≦ θ ≦ θ 1/} 2 + θ 6 + θ 3 is Sainkamu curve expressed by the following equation (1) is used.

_{r = p 1 + q 1 sin} (α 1 θ + β 1) ··· (1) It should be _{noted, p 1, q 1, α} 1, β 1 is a constant factor that is selected as appropriate.
The curve represented by equation (1) is shown as C ₄ in FIG.

- [theta] ₁ / The angular range of _{2-θ 2 ≧ θ ≧ θ} 1/2 + θ 6 + θ 3 -π is Sainkamu curve expressed by the following equation (2) is used.

r = p ₂ + q ₂ sin (α ₂ θ + β ₂ ) (2) Note that p ₂ , q ₂ , α ₂ and β ₂ are constant coefficients that are appropriately selected.
The curve represented by equation (2) is shown as C ₂ in FIG.

Also, the angle range _{θ 1/2 + θ 6 +} θ 3 ≦ θ ≦ π-θ 1/2-θ 2
The curve of the 180 ° rotational symmetry of Sainkamu curve represented by the formula (2) is used, the angle range _{θ 1/2 + θ 6 +} θ 3 -π
_{≧ θ ≧ θ 1/2 +} θ is 180 ° rotationally symmetrical curve of Sainkamu curve represented by the ₆ - [pi] Equation (1) is used.

Cubic curve represented by the angle range _{θ 1/2 ≦ θ ≦ θ} 1/2 + θ 6 following formula (3) is used.

r = a ₀ + a ₁ θ + a ₂ θ ² + a ₃ θ ³ (3) Note that a ₀ , a ₁ , a ₂ , and a ₃ are constant coefficients that are appropriately selected. The curve represented by equation (3) is shown as C ₃ in FIG.

The tertiary curve expressed by the angle range _{-θ 1/2-θ 2 ≦} θ ≦ -θ 1/2 the following equation (4) is used.

r = b ₀ + b ₁ θ + b ₂ θ ² + b ₃ θ ³ (4) Note that b ₀ , b ₁ , b ₂ and b ₃ are constant coefficients that are appropriately selected. The curve represented by equation (4) is shown by C ₁ in FIG.

The angular range _{π-θ 1/2 ≧ θ} ≧ π-θ 1/2-θ 2 in Formula (4)
In the curve of the 180 ° rotational symmetry of the cubic curve represented is used, the 180 ° rotational symmetry of the cubic curve represented by an angular range _{π + θ 1/2 ≦ θ} ≦ π + θ 1/2 + θ 6 in Formula (3) curves Used. That is, the angular range of the inner peripheral surface of the cylinder 3 is 0 ° ≦
The curved shape in θ <π and the curved shape in the angular range π ≦ θ <2π are 180 ° rotationally symmetric, and the seal region S ₁ ,
The sealing action in S ₂ and the sliding action of the vane 8 in the vicinity of both seal regions S ₁ and S ₂ are the same. Therefore, only the seal area S ₁ side shown in FIG. 2A will be described.

As shown in FIG. 4, the angular range −θ ₁ / 2−θ ₂ ≦ θ ≦ −θ ₁
When the equation (4) representing the curve C _{1 of} / 2 is differentiated by the angle θ, a curve D ₁ represented by the following equation (5) is obtained.

r ′ = b ₁ + 2b ₂ θ + 3b ₃ θ ² (5) Further, if the equation (2) representing the sine cam curve connected to the curve C ₁ is differentiated by the angle θ, the curve represented by the following equation (6) It becomes D ₂ .

r ′ = q ₂ α ₂ cos (α ₂ θ + β ₂ ) (6) The constant coefficients of the equations (2), (4), (5), and (6) are the angles θ.
_{= -Θ 1/2, -θ 1} /2-θ 2, θ 1/2 + θ 2 + θ 3 -π, is determined based on the set value of the radius r and the differential value r when 'the formula (2) , (4), the curves C ₂ and C ₁ are identified. When specifying the curves C ₂ and C ₁ , the continuity of the differential curves D ₂ and D ₁ and the differentiation of the differential curve D ₁ and the arc curve C ₀ (= 0)
And the cubic curve C ₁ is a sine cam curve C ₂
And smoothly connect to the arc curve C ₀ . As a result, the vane 8 moves from the cylinder inner peripheral surface of the sine cam curve C ₂ to the cubic curve C ₁
Of the cubic curve C ₁ smoothly moves to the cylinder inner circumferential surface of the circular arc curve C ₀ without being separated from the cylinder inner circumferential surface of the vane 8 by the discontinuous sliding contact of the vane 8. Damage to the inner surface is avoided. That is, the area of the cubic curve C ₁ is the buffer area X ₁ .

The dashed line curve C in 2,4 Figure _'2 is part of Sainkamu curve C _2, in the conventional this chain line curve C' are connected ₂ to an arc curve C _0, the angular range -θ ₄ ≦ θ ≦ θ ₅ is a seal area. The derivative of the chain line curve C ′ ₂ is shown by the chain line curve D ′ ₂ and a discontinuity occurs at θ = −θ ₄ . That is, conventionally, when θ = −θ _{4, the} inner peripheral surface of the cylinder becomes a corner portion, and the acceleration of the vane 8 in this direction is large at this portion, and in this embodiment, discontinuous sliding contact of the vane 8 occurs. Get up. However, in this embodiment on discontinuous sliding is eliminated by intervention of the buffer region X _1, buffer region X ₁ and the second view (a)
As is clear from the above, the angular range of the seal area S ₁ can be expanded.

The curve D ₄ shown in FIG. ₄ is a differential curve of the sine cam curve C ₄ , and the curve D ₃ is a differential curve of the cubic curve C ₃ . The chain line curve C ′ ₃ is a part of the sine cam curve C ₄ , and the chain line curve D ′ is
₄ is a differential curve of the broken line curve C _'3. That is, a cubic curve
The region of C ₃ is smoothly connected to the sealing region S ₁ and the sine cam curve C ₄ , and the region X ₂ provides the same cushioning effect as the cushioning region X ₁ .

Further, since the extension boundary d ₁ on the rear side of the introduction groove 11a in the rotation direction P of the rotor 6 is set on the boundary of the seal region S ₁ , the vane 8 is formed in the state of being close to the extension boundary d _1. The volume of the compression chamber R ₁ thus set becomes almost zero, and overcompression of the refrigerant gas is avoided. Introducing groove 11 that avoids such over-compression
Since the position of the boundary d _2, d _3, d ₄ of a is set based on the magnitude relation between the area sigma ₂ in area sigma ₁ and passes sectional Cs ₂ in the pass section Cs ₁ as described above, Cross section Cs
The ejection resistance at ₁ is less than or equal to the ejection resistance at the cross section Cs ₂ . Therefore, the discharge resistance in the passing cross section Cs ₂ immediately before the refrigerant gas reaches the introduction groove 11a and the boundary of the introduction groove 11a
The balance with the discharge resistance on d ₂ , d ₃ , and d ₄ is appropriate. Therefore, under this proper balance setting, it is appropriate that the discharge resistance in the passage cross section Cs ₂ is appropriately suppressed and that the communication between the adjacent compression chambers R ₁ and R ₂ via the vanes 8 is appropriate. If the position of the extension boundary d ₂ is set so as to be performed in the above manner, it is possible to improve the compression efficiency while achieving a smooth ejection action.

Furthermore, the interposition of the introduction groove 11a increases the degree of freedom in setting the discharge port 11A in the rotation direction of the rotor 6, and
Properly bring A to the seal area S ₁ side to extend the discharge valve 12A,
Bending fatigue of the discharge valve 12A can be reduced.

Of course, the present invention is not limited to the above-described embodiment, and for example, a sine cam curve and a circular arc curve may be approximately smoothly connected with a cubic curve, or a sine cam curve may be changed from a monotone increase to a monotone decrease. It is also possible to use another curve having a convex shape in place of the sine-cam curve, or to adopt a curve approximate to a cubic curve. Further, the structure in which the buffer area is provided only on the discharge port side can ensure a sufficient seal area and allow smooth sliding contact of the vanes. Furthermore, it is also possible to slightly shift the extension boundary on the rear side of the introduction groove from the boundary of the seal region, or to appropriately change the boundary shape of the introduction groove.

The present invention can also be applied to a fixed capacity vane compressor.

[Effect of the Invention] As described in detail above, the present invention provides a buffer for smoothly connecting at least a discharge area and a suction area, which are adjacent to each other with a seal area interposed therebetween, to a seal area and an upwardly convex curved area. Since the region is interposed, discontinuous sliding contact of the vane is eliminated, and damage to the cylinder inner peripheral surface can be prevented. In addition to this, the introduction groove connected to the discharge port is appropriately extended in the rotation direction of the rotor, and the passage cross section on the boundary of the introduction groove is on the cylinder inner peripheral surface along the extension boundary on the front side of the introduction groove. Since the cross-sectional area is equal to or larger than the passing cross-sectional area, the discharge resistances in both passing cross-sections are balanced, and the excellent effect that a smooth discharging action can be achieved is achieved.

[Brief description of drawings]

The drawings show an embodiment embodying the present invention. FIG. 1 is an enlarged sectional view taken along the line AA of FIG. 3, FIG. 2 (a) is an enlarged sectional view of an essential part, and FIG. 2 (b) is FIG. 3 is a side cross-sectional view of an enlarged perspective view of an essential part, and FIG. 4 is a graph showing a curve of a cylinder inner peripheral surface and a differential curve thereof. Cylinder 3, the rotor 6, the vanes 8, the suction port 10A, 10B, the discharge port 11A, 11B, guide grooves 11a, 11b, extending boundary d _1, d _2, the boundary d _3,
d ₄ , passage sections Cs ₁ and Cs ₂ , seal areas S ₁ and S ₂ , buffer area X ₁ .

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-170579 (JP, A) JP-A-57-116189 (JP, A) JP-A-58-98689 (JP, A) Actual development Sho-56- 76186 (JP, U)

Claims (1)

[Claims] 1. A cylinder-shaped rotor is rotatably fitted and housed in a cylinder, and the length of a radius vector from a rotation axis of the rotor to an inner peripheral surface of the cylinder is monotonically increased and monotonically decreased. A space between the cylinder inner peripheral surface of the curved area and the rotor peripheral surface is partitioned into a plurality of compression chambers by a plurality of vanes, and the rotation of the rotor sucks the refrigerant gas,
In a vane compressor that performs compression and discharge, a radius substantially matching the radius of the rotor is provided on the cylinder inner peripheral surface between the discharge port arranged at the end of the convex curved region and the suction port adjacent to the discharge port. A seal area having an arc curve is provided, and a buffer area formed by a curve smoothly connecting to the arc curve and the convex curve of the seal area is provided on the inner peripheral surface of the cylinder between the seal area and the discharge port. A guide groove extending forward and backward in the rotation direction of the rotor is connected and formed, and an extension boundary on the rear side of the guide groove is set near the boundary of the seal region so that the boundary between the guide groove and the rotor is The vane compressor in which the boundary position of the introduction groove is set such that the passage cross-sectional area is equal to or larger than the passage cross-sectional area between the rotor and the inner peripheral surface portion of the cylinder corresponding to the extension boundary on the front side of the introduction groove.